Chain saw guard



May 19, 1953 A. woLEsLAGLE CHAIN SAW GUARD Filed Feb. 7, 1951 Nw Nm.es.. M

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May 19 1953 A. woLEsLAGLl-z v2,638,944

CHAIN sAw GUARD Filed Feb. 7, 1951 3 Sheets-Sheet 3 L\ KM 5S w PatentedMay 19, 1953 UNITED STATES PATENT OFFICE Arnold Woleslagle, Geneseo, N.Y.

Application February '7, 1951, Serial No. 269,716

1o Claims. (o1. 14s- 32) This invention relates to a guard for powerdriven saws of the kind commonly7 known as chain saws.

An object of the invention is the' provision of 'a generally improvedand more satisiactory guard for saws of this kind.

Another object is the provision or" a practicable chain saw guardsufc'iently light and compact so as not to interfere substantiallj,7with lthe proper use of the saw, while at the same time giving adequateprotection against injury to the operator.

Still another object is the provision of a chain saw guard so designedand constructed as to be practical for use when the saw is taken aloft,lup a tree or pole. v f

A further object is the provision of a chain saw guard so designed 'andconstructed 'that itrnay Ibe applied. to certain types of existing chainsaws, as well as to rthose hereafter built, and may be lreadily removedfrom the saw when desired.'

These and other desirable objectsv may be attained in the mannerdisclosed. as an illustrative embodiment of the invention in thefollowing description and in the accompanying' drawings forming a parthereof, Ain which: Y

Fig. 1 is a view partly in side velevation and partly in `verticalsection taken longitudinally through a saw guard in accordance with apreferred embodiment of the present invention, as applied Ito a chainsaw of conventional construction, the guard being fully exten-ded to itsnormal position lprotecting the full length of the saw;

Fig. 2 is aside elevation of the guard removed from the saw; f

Fig. 3 is aside view somewhat similar to Figs. 1 and 2, butV with thesaw being used to saw through a piece of wood, and with the guardpartially collapsed to permit such sawing;

Fig. l is a top plan View of the saw guard removed from the saw and infully extended position;

Fig. 5 is a. longitudinal section taken centrally through the jointbetween two of the sections of a guiding or supporting tube ofthe sawguard;

Fig. 6 `is a fragmentary section taken longitudinally through the upperpart of the saw guard showing the upper guiding or supporting tube andthe upper part of the casing or guard members in collapsed position; 1

' Fig. '7 is a front face view of the bucking bar at the forward end ofthe guard;

Fig. 8 is a transverse section taken approximately on the line 8 8 ofFig. 2; and

Fig. 9 is a transverse section taken approximately on the line 9--9 ofFig. l.

The same reference numeralsv throughout the several views indicate thesaine parts. y

Chain saws are well known, and are made by a number vof 4differentmanufacturers, in various sizes and forms, some being driven by internalcombustion engines and some .being driven by electricrmotors. In thespecific embodiment here shown as an example, the saw guard of thepresent invention is applied to one known form of chain saw, but it willbe understood that by varying the details of the parts-of the presentsaw guard. which directly contact with the stationary frame parts of thesat/'fthe saw guard of the present invention may be adapted to variousother kinds, styles and sizes of saws.

Referring first to Fig. l of the drawingsotnere is shown somewhatdiagrammatically certain parts of a known commercial form of chain sawincluding a housing 2l containing the driving motor, a rear hand grip orhandle 23, and a bracket 25 to which is secured a cross bar 2 forming anup-perhandle for supporting the machine. The motor within the casing 2|drives Aa sprocket 29 over which runs a chain 3| having saw teeth formedthereon in known manner, the 'chain running over a fixed plate-likeguide the forward end of which is shaped approximately as a semicircle,as shown.

All of this is well known, and the details thereof may take variousforms, as above indicated. To this conventional structure, the guard ofthe present invention is added. This guard includes abucking bar forcontact with the work to be cut, suitable guides or supports forguidingthe bucking bar in its retracting and advancing movements, -and aguard casing associated with the bucking barA and guides for guardingthe saw chain against accidental lateral contact with other objects.

' In the preferred form, the guides comprise a pair of telescoping tubesindicated infgeneral at 4| and v43 respectively extending longitudinallyabove the top and below the bottom of the saw chain 3|. substantiallyidentical construction and a description of one will suffice for both.Each tube comprises a xed base section i5 rigidly but detachablyfastened to the motor casing 2| or other lined part of the sawmechanism, and a pluralityy The top and'bottom tubes maybe of 3 forcontact with the log, limb, or other article to be cut, and which has aslot 55 of sucient dimensions so that, when the guides 4| and 43 aretelescopically collapsed, the bucking bar 53 may move rearwardly (to theleft when viewed as in Fig. 1) in a direction axially of the saw, withthe saw chain projecting forwardly through the slot 55.

Each ofthe telesoping guides 4| and 43 may have anyfdesire'dliuberofsections.' "Merely as an example, threel movable sections 41, 49, and 5|are here illustrated, in addition to the fixed section 45. Each sectionexcept the forward section 5| has a relatively narrow inwardly `directedflange 6| (Fig. 5) at its forward end', and a second inward flange 63 yalittletothe rear of its forward end. Also, .each sectionexcept the rearxed section 45 has an 'outwardly directed flange 65 at its rear end. Theperiphery of the rear flange 65 of each section fits snugly but slidablywithinl the vinterior diameter-of the next larger tube section, and theinterioredges of the flanges 6| and 63 of each section fitsnug- 1y butslidably-on the exterior diameter of the next smaller section. Thus thesectionsL may move axially and telescopically with respect to eachother,the maximum limit of extension in each case being determined byengagement of the flange- 65 of the smaller tube with the flange 63ofthe next larger tube, as indicated in Fig. 5. i. The forward end ofthe front guide tube section` 5| is provided with a somewhat widerinwardly directed ange-61 which is apertured and threaded to 'receive ascrew 69 which fastens the bucking bar 53 to the front end of the tubesection 5|.

. The rear end of the rearmost or xed tube section 45 is provided withaplug 1| held.y in place in V,any suitablel manner (for example, by theradialfscrews 13) through which plug is threaded a longnadjusting screw15 which may be `turned by `-an external head 11 and held by a locknut19. The forward end of this screw,y 15 bears against'a follower block 8|movable longitudinal- 1y inthe tube 45, which block thrusts forwardlyagainst the rear end of a long coil compres,- sion spring 83,- whichextends all the way through all of the tube sections and reacts at itsforward 'end against the flange 61 at the front of the tube section 5|.lThe two springs 83 inthe two guides 4| and 43 thus constantly tend topush the bucking bar 53 forwardlyv to af position justin frontof theextreme front end of the saw chain (as shown in Fig. 7) in whichposition the respective fianges 63 and 65 of therespective guidesections are in contact with each other. But force exerted'rearwardlyagainst the bucking bar `53 (as for example when thesaw is thrustforwardly against a tree limb or other objectlwill telescope the guidetube vsections within each other and will cause the bucking bar to moverearwardly to some such position as illustrated in Fig. 3. The degree ofresistance to rearward movement of the bucking bar can be varied byadjustingthe screws 15.,

Surrounding the saw chain and thetelescopic guides 4| and 43 intransverse enveloping relationithereto, is a telescopic guard casinghaving a plurality of sections movable relative to each other as thebucking bar moves forwardly or rearwardly. Any desired number of lsuchguard sections may be used, there being eleven such sections in the formhere illustrated, numbered from the largest rear section to the smallestfront section, respectively, by the numerals 89 to 99, inclusive.

The front section.99 is secured 4 to the rear face of the bucking bar 53by means, for example, of screws l0! passing through inturned flanges atthe front end of the section 99, and threaded into the rear face of thebucking bar. The rear section 89 is fixed by brackets |05 to a plate |01which extends between and is fixed to the upper and lower guides 4| and43, as seen in Fig. 8. In longitudinal cross section` (viewed as inFig. 1) each guard casing section 89 'to `99,"inclusive, is slightlytapered, with its larger end rearwardly, and lwith the ,larger end ofeach section fitting suiciently snugly in the smaller end of the nextlarger section so as to prevent complete withdrawal of each section fromthe next one. In transverse dimensions (viewed as in Figs. 8 and 9, forexamp le) each section has approximately flat side w'allsvand'appro'ximately semicircular top and bottomv walls, of a size toenclose completely (in a transverse sense) the guide tubes 4| and 43 andthe saw mechanism between them. l

The springs 83, normally extending the guide tubes to their forwardpositions, will likewise extend the guard casing sections 89 to 99 totheir guarding or protecting positions shown in Figs.. 1, 2, and 4,wherein the forward part `of the chain saw is completely enclosed andany lateral movement of the saw toward an object will simply'result inlengagement of the object with the exterior of one or another of thecasing sections 89 to 99, without causing any cuttingof or other damageto such object.- But if it is desired purposely to cut some object, suchas the log or limb'indicated diagrammatically at lll in Fig. 3, then thesaw, instead of being moved laterally into engagementwith the log- |||,4is moved longitudinally into engagement Awith it. The `Alongitudinallthrust will cause rearward pressure ofthe log' against the front faceof the bucking bar 53,- which `will telescopically col-A lapse the`guide tube sections 41-5I andthe protecting casing'sections'S-SS toasufficient -ex; tent so that a sufficient part of the-chain saviaprojects beyond vthe front faceof the ybuckingv bar, to effect thedesired-cut. A Thisis well illus-Y trated inFig; 3, and the collapsedposition ofthe parts'is shown in'greater detailirl-Fig.V 6. soon as the-cutis" -completed `andthe .saw'fis lifted so that the bucking bar 53 isno longer-in contact with thefobject the^springsi83 auto-y matically andimmediately :restore the guide partsfand protecting casing parts vto-their forward positions, fully protecting ythe saw from J accidentalcontact with any other object. f ,f ."An arcuate guard plate |2|(Figari-3) extends around the rear side of the sprocket 29 and Dro-ltects this part ofthe mechanism against acci.-v -dental contact, the topandv bottom endsof'the plate |2| being fixed to the tubes 4| `and 43;

As already mentioned, the guard parts ofthe present invention may besecured to the convene; tional saw'mechanism in any desired manner.Merely as an example, the parts of the present;- guardinechanismmay ybesupported-flargely or' entirely from the plate |01 (Fig. 8) whichfiasabovestated, is in Iturn fixed to the tubes '4| and- 43 andflxedfthrough Itl'ie'braclsets |05,tothe, casing section 89. This plate|01,'inturn, mayY be secured lto any fixed p-arts of the conventionalsaw mechanism by'means of bolts or screws '125 (Fig. l) passing throughholes |21 (Fig."8) fin" the plate |01and inito suitable fixed parts ofthe saw mechanism., Y -vg It is seen from the foregoing disclosureI thatthe above mentioned objects of the invention 'are well ffullled, It isto be understood that the foregoing disclosure is given by way ofillustrative example only, rather than by way of limitation, and thatwithout departing from the invention, the details may be varied withinthe scope of the appended claims.

What is claim-ed is:

1. A chain saw guard comprising a pair of guide members extendingapproximately parallel lto each other, each comprising a plurality oftelescoping sections and adapted to receive an elongated chain sawbetween them, a front plate mounted on one end of said guide members andhaving an opening through which a chain saw may pass when said guidemembers are telescopically collapsed, and a guard structure associatedwith said guide members and front plate for protecting a cli-ain sawagainst lateral contact with an external obj ect.

2. A structure as defined in claim 1, in which said guard structuretransversely embraces said guide members and a saw between said guidemembers.

3. A structure as defined in claim l, in which said guard structureincludes a lplurality of tubular wall sections Itelesoopically arrangedwith respect to each other and embracing said guide members.

4. A structure as defined in claim 1, in which spring means is providedto urge said guide members and guard structure to maximum length.

5. A guard =for chain saws of the type including a fixed part and atoothed chain extending longitudinally in upper and lower reachesforwardly from lthe general Vicinity of said fixed part, said guardcomprising a bucking bar extending generally transverse to thelongitudinal directions of said upper and lower reaches of said chain,means for supporting said bucking bar from said fixed part for movementrelative thereto in said longitudinal directions and for holding saidbucking bar against substantial movement ltransverse to saidlongitudinal directions, and collapsible and extensible guard meanssupported from and extending between said xed part and said .bucking barfor Iprotecting that part of the chain Cil wLhich is between said fixedpar-t and said bucking bar from lateral contact with other objects, thebuckingbar being directly connected to the fixed part independently ofthe guard means.

6. A structure as defined in claim 5, further including resilient meansnormally tending to move said bucking bar forwardly toward the forwardend of said chain.

'7. A struc-ture as defined in claim 5, in which said bucking bar isconnected to the fixed part by a plurality of tubular guide sectionsindependently of the guard means and telesco-pically arranged withrespect to each other and extending from said fixed part to said buckingbar.

8. A structure as defined in claim 5, in which said means for supportingsaid bucking -bar includes two groups of tubular guide sections, thesections in each group being telescopically arranged with respect toeach other and extending from said xed part to said bucking bar, theguide sec-tions of one group being arranged on the outer side of onereach of said chain and the guide sections of the other group beingarranged on the outer side of the other reach of said chain.

9. A structure as dened in claim 8, further including a coil compressionspring extending through the sections of each group and tending to movesaid bucking bar .forwardly with respect to said fixed part.

10. A structure as defined in claim 5, in which said guard meansincludes a plurality of ringlike members of non-circular cross sectionarranged in telescopic relation to each other and extendingsubstantially from said fixed part to said bucking bar in embracingrelation to the portion of said chain located between said fixed partand said bucking bar.

ARNOLD WOLESLAGLE.

References Cited in the file of this patent UNITED STATES PATENTS Date

